EARTH SCIENCE
VOLCANOES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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pressure builds up inside the Earth
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lava from the eruption cools to form new crust
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magma rises through cracks in the Earth’s crust
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magma explodes to the surface
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Detailed explanation-1: -1. Divergent plate movement: This occurs when two lithospheric plates move away from each other. This causes gaps and cracks at the plate boundaries. Magma from the mantle of the Earth rises through these cracks, cools and solidifies to form a new crust.
Detailed explanation-2: -At first, during the eruption, magma or molten rocks rise above the surface. The formation of magma takes place when the Earth’s mantle melts. Such melting occurs due to the high pressure exerted on them. Such pressure is caused by the movement of tectonic plates, either pulling apart or pushing towards one another.
Detailed explanation-3: -Noticeable steaming or fumarolic activity and new or enlarged areas of hot ground. Subtle swelling of the ground surface. Small changes in heat flow. Changes in the composition or relative abundances of fumarolic gases.